Photoluminescence properties of cadmium-selenide quantum dots embedded in a liquid-crystal polymer matrix

Journal Article · Wed May 15 04:00:00 EDT 2013 · Semiconductors

DOI:https://doi.org/10.1134/S1063782613050217· OSTI ID:22126570

Timoshenko, V. Yu. ^[1]; Plenge, J.; Ruehl, E. ^[2]; Shatalova, A. M.; Shandryuk, G. A.; Merekalov, A. S.; Tal'roze, R. V. ^[3]

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1. Moscow State University, Faculty of Physics (Russian Federation)
2. Free University of Berlin, Institute of Chemistry and Biochemistry (Germany)
3. Russian Academy of Sciences, Topchiev Institute of Petrochemical Synthesis (Russian Federation)

The photoluminescence properties of cadmium-selenide (CdSe) quantum dots with an average size of {approx}3 nm, embedded in a liquid-crystal polymer matrix are studied. It was found that an increase in the quantum-dot concentration results in modification of the intrinsic (exciton) photoluminescence spectrum in the range 500-600 nm and a nonmonotonic change in its intensity. Time-resolved measurements show the biexponential decay of the photoluminescence intensity with various ratios of fast and slow components depending on the quantum-dot concentration. In this case, the characteristic lifetimes of exciton photoluminescence are 5-10 and 35-50 ns for the fast and slow components, respectively, which is much shorter than the times for colloidal CdSe quantum dots of the same size. The observed features of the photoluminescence spectra and kinetics are explained by the effects of light reabsorption, energy transfer from quantum dots to the liquid-crystal polymer matrix, and the effect of the electronic states at the CdSe/(liquid crystal) interface.

• OSTI ID: 22126570
• Journal Information: Semiconductors, Journal Name: Semiconductors Journal Issue: 5 Vol. 47; ISSN SMICES; ISSN 1063-7826
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
CADMIUM SELENIDES
CONCENTRATION RATIO
DECAY
ENERGY TRANSFER
INTERFACES
KINETICS
LIFETIME
LIQUID CRYSTALS
PHOTOLUMINESCENCE
POLYMERS
QUANTUM DOTS
SPECTRA